What this RFC defines
RFC 2369 defines a set of email headers for automating mailing list management: List-Unsubscribe, List-Subscribe, List-Help, List-Post, List-Owner, and List-Archive. Each header contains a URL or mailto: address where subscribers can perform the corresponding action without searching for links in the message body.
Where you see it in practice
The List-Unsubscribe: header that email clients use to show an Unsubscribe option in the message header area comes from RFC 2369. Gmail’s unsubscribe link displayed above newsletter emails reads the List-Unsubscribe header defined here. ESP platforms automatically add these headers to campaign emails. RFC 8058 later added the one-click POST mechanism as a complement to RFC 2369’s mailto: and HTTP approaches.
How it connects to other RFCs
RFC 2369 is complemented by RFC 8058, which adds the List-Unsubscribe-Post header for one-click unsubscribe via HTTP POST. Both headers are typically included together in marketing emails. RFC 2919 (List-Id) is a related header that identifies the list itself, often included alongside RFC 2369 headers.
Current status
RFC 2369 is a current standard, published July 1998. The List-Unsubscribe header it defines is universally supported by ESPs and is read by Gmail, Outlook, Apple Mail, and Yahoo. Google and Yahoo’s February 2024 bulk sender requirements explicitly cite List-Unsubscribe support as mandatory for bulk senders.
List command URLs
RFC 2369 defined the List-* header family for mailing list messages: List-Help (URL for help documentation), List-Subscribe (URL to subscribe), List-Unsubscribe (URL or mailto: to unsubscribe), List-Post (address to post to the list), List-Owner (address of the list operator), and List-Archive (URL of the list archive). These headers let email clients present list-management options to users without requiring the user to remember or find the correct commands.
List-Unsubscribe evolution
The List-Unsubscribe header defined here has become critical for deliverability. Gmail, Outlook.com, and Yahoo require it on bulk mail, and its absence contributes to spam-folder placement. Originally, List-Unsubscribe accepted a mailto: URL or a HTTPS URL; RFC 8058 later added a one-click variant (List-Unsubscribe-Post: List-Unsubscribe=One-Click) that lets receivers process unsubscribes without user round-trips. Any bulk sender that omits List-Unsubscribe in 2026 is at serious deliverability disadvantage.
Client behavior
Gmail displays a prominent “Unsubscribe” button in the header when List-Unsubscribe is present. Outlook.com shows a similar unsubscribe prompt. Apple Mail on iOS 16+ displays “Unsubscribe” in the message header for detected mailing list messages. This UX makes it far easier for users to unsubscribe than to mark as spam, which improves both user experience and sender reputation. Correctly-implemented List-Unsubscribe measurably reduces spam-complaint rates.
RFC 2369 (July 1998) defines the List-* URL header family: List-Help, List-Unsubscribe, List-Subscribe, List-Post, List-Owner, List-Archive. Each carries one or more URLs (mailto: or http/https) that clients render as buttons or links, letting users take list-related actions with one click. Foundation for the “Unsubscribe” button visible in every modern mail client. Companion to RFC 2919 List-Id. Extended by RFC 8058 for one-click unsubscribe automation (mandatory since Gmail/Yahoo 2024 bulk sender requirements).
RFC 2369 at a glance
| Aspect | Detail |
|---|---|
| Purpose | Machine-readable URLs for list actions (subscribe, unsubscribe, help, post, archive) |
| Headers introduced | List-Help, List-Unsubscribe, List-Subscribe, List-Post, List-Owner, List-Archive |
| URL scheme | mailto: (send an email) or http/https (visit a URL) |
| Multiple URLs per header | Yes, comma-separated angle-bracketed; client picks preferred scheme |
| Companion RFCs | RFC 2919 List-Id, RFC 8058 One-Click Unsubscribe |
| Published | July 1998 |
The six List-* headers
| Header | Purpose | Typical URL |
|---|---|---|
List-Help | Documentation, FAQ, or help for the list | mailto:help@list.example.com or https://example.com/help/list |
List-Unsubscribe | Remove from list | mailto:unsubscribe@list.example.com or https://example.com/unsub?token=abc |
List-Subscribe | Add to list | mailto:subscribe@list.example.com or https://example.com/subscribe |
List-Post | Send a message to the list | mailto:post@list.example.com |
List-Owner | Contact the list owner | mailto:owner@list.example.com |
List-Archive | Browse the list archive | https://example.com/archive/list |
Header format examples
One-Click Unsubscribe (RFC 8058 extension)
List-Unsubscribe-Post: List-Unsubscribe=One-Click, letting the client POST to the URL directly without user interaction. This is the mechanism behind Gmail’s “Unsubscribe” button in the toolbar. Bulk senders (5000+ messages/day per Gmail’s threshold) must implement both RFC 2369 and RFC 8058 to remain deliverable.Common List-* implementation mistakes
Related standards and further reading
- RFC 2919 List-Id Guide: identifier header
- RFC 8058 One-Click Unsubscribe: modern requirement
Frequently asked questions
Is List-Unsubscribe required for bulk email?
Yes, since Gmail and Yahoo’s February 2024 bulk sender requirements. Senders with 5000+ messages per day per Gmail’s threshold must emit List-Unsubscribe (RFC 2369) and List-Unsubscribe-Post (RFC 8058 one-click). Failing to comply results in reduced deliverability to Gmail and Yahoo inboxes; both are large enough that non-compliance materially impacts reach.
Should I use mailto: or HTTPS for List-Unsubscribe?
Both. Emit HTTPS as the primary (works from webmail, mobile, any browser); include mailto: as fallback (some clients prefer it). Client picks the preferred scheme per RFC 2369. Modern clients (Gmail, Outlook, Apple Mail) generally prefer HTTPS. Providing both maximizes compatibility.
What is the difference between List-Post and the From address?
From is the message’s stated author; List-Post is the address to post NEW messages to the list. On a mailing list, From is typically the individual poster’s address (or the list rewriting From for DMARC alignment); List-Post is the list’s post address (e.g., list@example.com). When a subscriber “replies to list” from their client, the client uses List-Post to determine the target address.
Can List-* headers appear on non-mailing-list mail?
Only List-Unsubscribe on legitimate marketing/newsletter mail from a single sender (not necessarily a discussion list). This is standard for ESP-sent bulk email. Other List-* headers imply a real list (List-Post, List-Subscribe, List-Archive make sense only for actual lists). Emitting all List-* headers on non-list mail can confuse mail clients.
Does List-Unsubscribe alone satisfy Gmail’s requirements?
No. Since February 2024, Gmail requires both List-Unsubscribe (RFC 2369) AND List-Unsubscribe-Post (RFC 8058 one-click). The one-click extension lets Gmail’s toolbar unsubscribe button POST directly without user interaction. RFC 2369 alone requires the user to click a URL, which is a step Gmail no longer accepts as sufficient for bulk sender compliance.
About the Author
Alaa · LinkedIn
Email infrastructure specialist with 8+ years of hands-on experience in SMTP, deliverability, and email verification. I’ve configured and troubleshot mail systems across Postfix, Exchange, and cloud relays, managed IP reputation and warmup campaigns, and built verification pipelines processing millions of addresses. My work spans DNS authentication (SPF, DKIM, DMARC, BIMI), bounce handling, blocklist monitoring, and compliance frameworks including CAN-SPAM and GDPR. I write every article on SMTPedia to give email professionals, developers, and marketers the accurate, RFC-grounded reference they need.
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